The present invention relates to a tempo setting apparatus for an electronic musical instrument, which sets the tempos of rhythms, such as an eight beat, waltz and mambo, and relates to a parameter setting apparatus for an electronic musical instrument, which sets various parameters.
Electronic musical instruments with a rhythm performance function have been developed and used. In such an electronic musical instrument, generally, plural pieces of rhythm performance data corresponding to a plurality of rhythms are previously stored in a memory so that the desired rhythm performance is automatically performed when a player selects a desired rhythm from those rhythms.
This will be explained more specifically. When a player selects a rhythm using a rhythm select switch and then operates a rhythm start switch to instruct the start of a rhythm performance, an automatic performance for the rhythm sounds (automatic rhythm performance) starts. When the automatic rhythm performance begins, a control section of the electronic musical instrument sequentially reads out rhythm performance data corresponding to the selected rhythm from the memory and sends the data piece by piece to a tone generator. The tone generator produces tone signals based on the rhythm performance data and sends the tone signals to a loudspeaker. Consequently, the rhythm sounds are produced from the loudspeaker automatically.
With such an automatic rhythm performance in progress, when the player manipulates a keyboard for a keyboard type electronic musical instrument or strings for a guitar type electronic musical instrument to instruct tone generation, the player can play a melody performance with the automatic rhythm performance on the background.
Individual rhythms have their own proper tempos (standard tempos) different from one another. It is experimentally known that whether the tempo for each rhythm is proper differs depending on the player's sense of rhythms. Conventionally, therefore, after selecting a rhythm and starting an automatic rhythm performance at its standard tempo, the player further manipulates a tempo setting device to tune the tempo based on the player's sense of rhythm.
A tempo setting apparatus is used to adjust the tempos. For example, this tempo setting apparatus comprises a tempo setting device of a rotary type such as a potentiometer and a display unit for displaying a tempo value set by this tempo setting device. For a keyboard type electronic musical instrument, the tempo setting device and the display unit are generally laid out on an operation panel located in front of a player for easier view. Accordingly, the player can operate the tempo setting device to set a desired tempo value while viewing the display unit.
With regard to, for example, a guitar type electronic musical instrument which is hung from the shoulder of a player when being played, the tempo setting device and the display unit often come to the blind position from the player during music playing. At the time of changing the tempo during music playing, it is difficult to know the standard tempo value for the rhythm, the current tempo value and the like. This hinders smooth alternation of tempos.
In the conventional tempo setting apparatus, the movable range of the tempo setting device is set to range from the minimum tempo value to the maximum tempo value. In some cases, the standard tempos value for some rhythms do not come near a tempo value corresponding to the middle point of the movable range of the tempo setting device, but come close to a tempo value corresponding to one end of that movable range. To alter the tempo value from the standard tempo value to a desired tempo value, the player should alter the position of the tempo setting device around the eccentric position corresponding to the standard tempo value and there is not much space to move the position of the tempo setting device to obtain the desired tempo value. This makes the tempo adjustment difficult.
In a conventional tempo setting apparatus comprising, for example, a tempo setting device of the rotary type, a minimum tempo value corresponding to one end of the tempo setting device and a maximum tempo value corresponding to the other end thereof are predetermined and fixed, for example, 30 and 250 beats per minute respectively, and the difference between the minimum tempo value and the maximum tempo value is large. Therefore, when a pointer of the tempo setting device alters infinitesimally, the tempo value alters significantly. Accordingly, the accuracy of setting the tempo value is not satisfactory when such a conventional tempo setting apparatus is used.
Electronic musical instruments generally have a special operation mode called "system set mode". This system set mode is used to set parameters. These parameters are used to select a timbre and the type of an acoustic effect, to indicate the degree of an acoustic effect, and the like. Parameters are normally set to an electronic musical instrument prior to music playing and the parameter setting is seldom executed during music playing. Therefore, the mode is seldom changed to the system set mode during music playing.
However, the mode may be changed from a music playing mode to the system set mode during music playing against the player's intention. To avoid such an event, a switch for changing the mode to the system set mode (hereinafter called "mode switch") is located where it is difficult for a player to touch the mode switch during music playing. The mode switch comprises, for example, two special switches which are selected from switches provided on the operation panel such as an UP/DOWN switch, a rhythm start switch, a rhythm select switch and the like. The mode is changed from the music playing mode to the system set mode only when the two switches are depressed simultaneously.
Even with the above arrangement, the mode switch may be depressed accidentally during music playing if the mode switch is located where the player has a difficulty in seeing it, as, for example, on a guitar type electronic musical instrument which is hung from the shoulder of the player. When such an event occurs, the mode is changed unexpectedly, causing the player to inevitably interrupt the music playing.
Normally, the player can confirm if an electronic musical instrument is in the system set mode by checking what is displayed on the display unit. For an electronic musical instrument without a display unit, however, the player may be late in noticing that the electronic musical instrument is set to the system set mode.